001    /*
002     * Copyright (c) 2007-2014 Concurrent, Inc. All Rights Reserved.
003     *
004     * Project and contact information: http://www.cascading.org/
005     *
006     * This file is part of the Cascading project.
007     *
008     * Licensed under the Apache License, Version 2.0 (the "License");
009     * you may not use this file except in compliance with the License.
010     * You may obtain a copy of the License at
011     *
012     *     http://www.apache.org/licenses/LICENSE-2.0
013     *
014     * Unless required by applicable law or agreed to in writing, software
015     * distributed under the License is distributed on an "AS IS" BASIS,
016     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017     * See the License for the specific language governing permissions and
018     * limitations under the License.
019     */
020    
021    package cascading.cascade;
022    
023    import java.util.Map;
024    import java.util.Properties;
025    
026    import cascading.property.Props;
027    
028    /**
029     * Class CascadeProps is a fluent helper class for setting various {@link Cascade} level properties passed
030     * through a {@link CascadeConnector}.
031     */
032    public class CascadeProps extends Props
033      {
034      public static final String MAX_CONCURRENT_FLOWS = "cascading.cascade.maxconcurrentflows";
035    
036      int maxConcurrentFlows = 0;
037    
038      /**
039       * Method setMaxConcurrentFlows sets the maximum number of Flows that a Cascade can run concurrently.
040       * <p/>
041       * A value of one (1) will run one Flow at a time. A value of zero (0), the default, disables the restriction.
042       * <p/>
043       * By default a Cascade will attempt to run all give Flow instances at the same time. But there are occasions
044       * where limiting the number for flows helps manages resources.
045       *
046       * @param properties         of type Map<Object, Object>
047       * @param numConcurrentFlows of type int
048       */
049      public static void setMaxConcurrentFlows( Map<Object, Object> properties, int numConcurrentFlows )
050        {
051        properties.put( MAX_CONCURRENT_FLOWS, Integer.toString( numConcurrentFlows ) );
052        }
053    
054      /**
055       * Creates a new CascadeProps instance.
056       *
057       * @return CascadeProps instance
058       */
059      public static CascadeProps cascadeProps()
060        {
061        return new CascadeProps();
062        }
063    
064      public CascadeProps()
065        {
066        }
067    
068      public int getMaxConcurrentFlows()
069        {
070        return maxConcurrentFlows;
071        }
072    
073      /**
074       * Method setMaxConcurrentFlows sets the maximum number of Flows that a Cascade can run concurrently.
075       * <p/>
076       * A value of one (1) will run one Flow at a time. A value of zero (0), the default, disables the restriction.
077       * <p/>
078       * By default a Cascade will attempt to run all give Flow instances at the same time, if eligible. But there are
079       * occasions where limiting the number for flows helps manages resources.
080       *
081       * @param maxConcurrentFlows of type int
082       */
083      public CascadeProps setMaxConcurrentFlows( int maxConcurrentFlows )
084        {
085        this.maxConcurrentFlows = maxConcurrentFlows;
086    
087        return this;
088        }
089    
090      @Override
091      protected void addPropertiesTo( Properties properties )
092        {
093        setMaxConcurrentFlows( properties, maxConcurrentFlows );
094        }
095      }